250 University of California Publications in Botany. [VOL. 3 



preserved at the Herbarium of the California Academy) the 

 achenes are narrowed at the base and some of the pappus-paleae 

 are brown, others smoky, at least those of the outer achenes con- 

 spicuously scabrous. 



The variations in pappus and in achenial characters color, 

 shape, pubescence, relative length of parts are so numerous that 

 any attempt to characterize and name the different forms of this 

 species would, if logically carried out, result practically in the 

 naming of individual specimens. A number of forms now at 

 hand are fully as distinct as many of those recently segregated 

 as species and the number could undoubtedly be greatly extended 

 by careful collection in western San Diego County. 



4. M. linearifolia (DC.) Schultz Bip., Pollichia xii.-xxiv. 308 

 (1866) ; Gray, Proc. Am. Acad. ix. 211 (1874). Calais lineari- 

 folia DC., Prodr. vii. 85 (1838). Uropappus linearifolius Nutt., 

 Trans. Am. Philos. Soc. ser. 2, vii. 425 (1841). Calais macro- 

 chaeta Gray, PL Fendl. 112 (1849). Microseris macrochaeta 

 Schultz Bip., I.e. 309; Gray, Proc. Am. Acad. ix. 211 (1874). 

 M. anomala Wats., Proc. Am. Acad. xxii. 475 (1887), and xxiv 

 84 (1889). 



Plant 1 to 4 or even 6 dm. high : stems or peduncles often sev- 

 eral from the base, erect, the peduncle in robust plants thickened 

 or fistulous under the oblong head: leaves linear (8 to 15 cm. 

 long, 1 to 5 mm. wide) and with 2 or 3 to several pairs of more 

 or less remote salient lobes or entire: achenes attenuate above 

 into a beak, usually black : pappus deciduous, from silvery white 

 to sordid, 12 to 15 mm. long, including the very delicate awn, this 

 about one-half the length of the deeply notched palea. 



Common throughout Southern California except on the higher 

 mountains ; north to British Columbia and east to New Mexico ; 

 ranging from the Lower Sonoran well into the Transition Zone. 



Mr. T. S. Brandegee 62 has pointed out that in this and related 

 species the awns of the pappus develope much earlier than the 

 paleae, attaining their full length by the time the flower opens ; 

 while the paleae, then many times shorter, increase in length un- 

 til the seed is mature, at which time they equal or exceed the 



62Zoe i. 126 (1890). 



